1. Field of the Invention
The present invention relates to a map distribution system used for a navigation terminal or the like that is mounted on a vehicle and its terminal device.
2. Background Art
A car navigation system mounted on a vehicle as a typical mobile body serves to display a map on display means on the basis of the measured current position of the vehicle and display a mark showing the current position of the vehicle on the map in a superimposed manner.
In the car navigation system, measuring means for measuring the current position of the vehicle comprises a GPS (global positioning system) receiver or a self-contained navigation sensor for calculating the current position from the travel distance and the advancing direction of the vehicle or the like. Further, map information for displaying the map on the display means, accompanying information accompanying the map information and various kinds of functional services are adapted to be provided from an information center located outside the vehicle by using communication means mounted on the vehicle.
As described above, in the car navigation system, the latest map information can be obtained from the information center located outside the vehicle by using the communication means mounted on the vehicle.
However, in order to obtain the latest map information, it is expected that a communication cost for using the communication means be generated.